The present invention relates to an atomizer for liquids or slurries, said atomizer having an annular slit nozzle and to a process in which such an atomizer is used for the partial or complete combustion of a hydrocarbon fuel.
The construction of an atomizer for the partial or complete combustion of large quantities of hydrocarbon fuels presents a number of design problems which arise on account of the specific nature of the combustion reaction and of the large quantities of hydrocarbon fuels which it is required to handle. Such an atomizer should be designed so as to provide the degree of atomization of the fuel required to ensure intimate mixing of fuel and oxygen thus obtaining a high yield of product gas and a low soot production. The design should also be such that the pressure differential across the atomizer required to obtain the required degree of fuel atomization is not prohibitively high.
In British patent specification 1470820 there is described an atomizer for an efficient atomization of fuel achievable at a low pressure differential across the atomizer. This known atomizer is provided with an annular slit nozzle wherein the width of the slit may be varied within a wide range during operation of the atomizer. This arrangement of the atomizer allows a readily adjustment or regulation of the slit to properly handle the fuel at different pressures and to discharge the fuel in the desired manner and in the desired quantities.
By varying the slit width it can be ensured that the fuel is ejected from the slit substantially in the extension of the slit and not at an angle to the said extension, resulting in a constant stream of atomized fuel globules issuing from the outlet slit. Further, the pressure differential across the slit can be kept rather moderate at high fuel throughput by varying the slit width. A very high pressure differential across the slit would necessitate the using of very high pressure fuel feed equipment which would make the atomizer economically unattractive.
In addition to the possibility of adjusting the slit size this known atomizer can also vary the pressure differential across the slit within a certain range and still obtain good atomization. By appropriate control of these two variables it is therefore possible to operate the atomizer over a wide range of fuel throughputs.